text: # Copyright 2015 The TensorFlow Authors. All Rights Reserved.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #     http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  # ==============================================================================
  """
  Top-level module of TensorFlow. By convention, we refer to this module as
  `tf` instead of `tensorflow`, following the common practice of importing
  TensorFlow via the command `import tensorflow as tf`.
  
  The primary function of this module is to import all of the public TensorFlow
  interfaces into a single place. The interfaces themselves are located in
  sub-modules, as described below.
  
  Note that the file `__init__.py` in the TensorFlow source code tree is actually
  only a placeholder to enable test cases to run. The TensorFlow build replaces
  this file with a file generated from [`api_template.__init__.py`](https://www.github.com/tensorflow/tensorflow/blob/master/tensorflow/api_template.__init__.py)
  """
  
  from __future__ import absolute_import as _absolute_import
  from __future__ import division as _division
  from __future__ import print_function as _print_function
  
  import distutils as _distutils
  import inspect as _inspect
  import logging as _logging
  import os as _os
  import site as _site
  import six as _six
  import sys as _sys
  
  from tensorflow.python.tools import module_util as _module_util
  from tensorflow.python.util.lazy_loader import LazyLoader as _LazyLoader
  
  # Make sure code inside the TensorFlow codebase can use tf2.enabled() at import.
  _os.environ['TF2_BEHAVIOR'] = '1'
  from tensorflow.python import tf2 as _tf2
  _tf2.enable()
  
  # API IMPORTS PLACEHOLDER
  
  # WRAPPER_PLACEHOLDER
  
  # Make sure directory containing top level submodules is in
  # the __path__ so that "from tensorflow.foo import bar" works.
  # We're using bitwise, but there's nothing special about that.
  _API_MODULE = _sys.modules[__name__].bitwise
  _tf_api_dir = _os.path.dirname(_os.path.dirname(_API_MODULE.__file__))
  _current_module = _sys.modules[__name__]
  
  if not hasattr(_current_module, '__path__'):
    __path__ = [_tf_api_dir]
  elif _tf_api_dir not in __path__:
    __path__.append(_tf_api_dir)
  
  # Hook external TensorFlow modules.
  # Import compat before trying to import summary from tensorboard, so that
  # reexport_tf_summary can get compat from sys.modules. Only needed if using
  # lazy loading.
  _current_module.compat.v2  # pylint: disable=pointless-statement
  try:
    from tensorboard.summary._tf import summary
    _current_module.__path__ = (
        [_module_util.get_parent_dir(summary)] + _current_module.__path__)
    setattr(_current_module, "summary", summary)
  except ImportError:
    _logging.warning(
        "Limited tf.summary API due to missing TensorBoard installation.")
  
  # Lazy-load estimator.
  _estimator_module = "tensorflow_estimator.python.estimator.api._v2.estimator"
  estimator = _LazyLoader("estimator", globals(), _estimator_module)
  _module_dir = _module_util.get_parent_dir_for_name(_estimator_module)
  if _module_dir:
    _current_module.__path__ = [_module_dir] + _current_module.__path__
  setattr(_current_module, "estimator", estimator)
  
  try:
    from .python.keras.api._v2 import keras
    _current_module.__path__ = (
        [_module_util.get_parent_dir(keras)] + _current_module.__path__)
    setattr(_current_module, "keras", keras)
  except ImportError:
    pass
  
  # Explicitly import lazy-loaded modules to support autocompletion.
  # pylint: disable=g-import-not-at-top
  if not _six.PY2:
    import typing as _typing
    if _typing.TYPE_CHECKING:
      from tensorflow_estimator.python.estimator.api._v2 import estimator
  # pylint: enable=g-import-not-at-top
  
  # Enable TF2 behaviors
  from tensorflow.python.compat import v2_compat as _compat  # pylint: disable=g-import-not-at-top
  _compat.enable_v2_behavior()
  _major_api_version = 2
  
  
  # Load all plugin libraries from site-packages/tensorflow-plugins if we are
  # running under pip.
  # TODO(gunan): Enable setting an environment variable to define arbitrary plugin
  # directories.
  # TODO(gunan): Find a better location for this code snippet.
  from tensorflow.python.framework import load_library as _ll
  from tensorflow.python.lib.io import file_io as _fi
  
  # Get sitepackages directories for the python installation.
  _site_packages_dirs = []
  _site_packages_dirs += [] if _site.USER_SITE is None else [_site.USER_SITE]
  _site_packages_dirs += [_p for _p in _sys.path if 'site-packages' in _p]
  if 'getsitepackages' in dir(_site):
    _site_packages_dirs += _site.getsitepackages()
  
  if 'sysconfig' in dir(_distutils):
    _site_packages_dirs += [_distutils.sysconfig.get_python_lib()]
  
  _site_packages_dirs = list(set(_site_packages_dirs))
  
  # Find the location of this exact file.
  _current_file_location = _inspect.getfile(_inspect.currentframe())
  
  def _running_from_pip_package():
    return any(
        _current_file_location.startswith(dir_) for dir_ in _site_packages_dirs)
  
  if _running_from_pip_package():
    # TODO(gunan): Add sanity checks to loaded modules here.
    for _s in _site_packages_dirs:
      # Load first party dynamic kernels.
      _main_dir = _os.path.join(_s, 'tensorflow/core/kernels')
      if _os.path.exists(_main_dir):
        _ll.load_library(_main_dir)
  
      # Load third party dynamic kernels.
      _plugin_dir = _os.path.join(_s, 'tensorflow-plugins')
      if _os.path.exists(_plugin_dir):
        _ll.load_library(_plugin_dir)
  
  # Add module aliases
  if hasattr(_current_module, 'keras'):
    losses = keras.losses
    metrics = keras.metrics
    optimizers = keras.optimizers
    initializers = keras.initializers
    setattr(_current_module, "losses", losses)
    setattr(_current_module, "metrics", metrics)
    setattr(_current_module, "optimizers", optimizers)
    setattr(_current_module, "initializers", initializers)
  # pylint: enable=undefined-variable
  
  # Delete modules that should be hidden from dir().
  # Don't fail if these modules are not available.
  # For e.g. this file will be originally placed under tensorflow/_api/v1 which
  # does not have 'python', 'core' directories. Then, it will be copied
  # to tensorflow/ which does have these two directories.
  # pylint: disable=undefined-variable
  try:
    del python
  except NameError:
    pass
  try:
    del core
  except NameError:
    pass
  try:
    del compiler
  except NameError:
    pass
  
  # __all__ PLACEHOLDER
  